The present invention relates to sheet folding machines of the very well known "buckle fold" type, in which a sheet of paper is advanced against a stop to cause buckling of the paper, with the buckle drawn between a pair of strategically located nip rollers to form a fold across the width of the paper sheet.
The reliability of such machines depends in large part on the incidence of skewing of the paper sheet with respect to the rollers as it is fed into the machines, particularly for one-at-a-time manual feed.
Such machines often include movable stops to enable different fold line locations to be achieved and also to allow selective control over the number of folds. Such movable stops do not define locating surfaces which are accurately squared to the direction of paper feed, precisely repeatable fold patterns are thus not ensured for machines having such adjustable fold pattern capability.
Versatility in accommodating various paper widths and fold patterns is of great usefulness, particularly if it can be achieved by a simple desk top machine. Manual squaring of the paper is usually required as it is fed, sometimes leading to inadvertent misalignment and less reliability in the folding action is thereby created.